1. Field of the Invention
This invention relates to a multi-purpose material handling machine and more particularly to a self-propelled mine vehicle having a telescoping boom adapted for efficient attachment and detachment to a multi-purpose bucket that is maneuverable by the extensible boom to a preselected position for conducting a variety of material handling operations in an underground mine.
2. Description of the Prior Art
In underground mining operations it is well known to utilize shovel and scoop-type machines in the handling and transportation of loose or mined material in the mine. U.S. Pat. Nos. 3,226,857 and 4,117,610 and Fed. Rep. of Germany Pat. No. 2,328,207 are examples of such devices. These devices, however, are confined generally to use in a bulldozing mode of operation to pick up a pile of loose material and transport the material to a location in the mine for unloading, such as onto a haulage belt or into a material haulage vehicle. Another disadvantage of these vehicles is the lack of maneuverability of the shovel or scoop in the limited working space of an underground mine to gather up, transport, and discharge the material. Furthermore, the manner in which the shovel or scoop is connected to the prime mover is generally complex and limits the versatility of the material handling machine for conversion to some other material handling operation in an underground, such as unloading the material at an elevated height above the prime mover or carrying out clamshell operations as when encountered in cleaning up a roof fall in an entry.
In the operations of sinking vertical shafts or caissons, as well as, sinking a shaft at an angle between the horizontal and vertical, mucking machines or excavators as disclosed in U.S. Pat. No. 2,949,201 are conventionally used. A mucking machine of this type has a swingable, telescoping boom with a clam mounted on the free end of the boom. The boom is operated for lateral swinging movement, as well as, for extending and retracting the boom to open and close the clam.
In the above referenced patent, the boom is pivotally mounted on a cage by vertical pins, and the cage pivotally supports the boom turntable. The boom swings laterally on the turntable by operation of piston cylinders. Additional piston cylinders are provided to lift the boom about a horizontal axis. Other similar mucking machines are disclosed in U.S. Pat. Nos. 2,067,879; 3,187,916; and 3,991,886. A major disadvantage of this type of machine is limited maneuverability in an entry, cross cut, or pillar section due to the complex linkage and control means for moving the clam into and out of position and to open and close the clam.
It is well known in above ground earth moving and excavation operations to combine in one machine the operations of earth collecting, transporting, and earth discharging with bulldozing operations. These machines are quite large as disclosed in U.S. Pat. Nos. 3,842,999 and 4,080,746 and are therefore not readily adaptable to undergrounding mining operations. Also the complex linkages connecting the bucket to the boom of an above ground excavating machine are undesirable from a maintenance standpoint for use in an underground mine.
Machines employed in underground mining operations must be capable of operating in areas of minimum overhead clearance. Consequently, the above ground earth excavating and transporting machines, as above described, are inoperable to perform the functions performed above ground in an underground mine. Therefore, there is a need for a multi-purpose material handling vehicle operable to carry out a wide variety of operations in an underground mine. The frame of the machine must have a minimum height to permit the vehicle to maneuver freely in the passageways of the mine. Once in position the material handling device must be freely maneuverable to engage the material to be transported or to clear a section by tramming of the machine. In addition the ability to convert a material handling machine from one use to another is advantageous in a mine.
With the conventionally known devices conversion is a problem because of the space limitations available for workmen to replace components on a machine. Also the presence of complex linkage connections between a bucket, for example, and the prime mover as encountered with conventional devices restricts the efficiency in converting a machine from one use to another. This problem leads to delays in the overall mining operation.
While it is known with above ground machinery to provide a quickly attachable and detachable loader bucket on the end of a boom of a prime mover as disclosed in U.S. Pat. Nos. 3,705,656; 3,845,871; and 4,187,050, the known quick disconnect devices are not efficiently operated in the limited space of an underground mine. The complex linkages of these devices are also vulnerable to frequent breakdown in the working environment of an underground mine.
While it has been suggested to provide multi-purpose buckets that are removably attachable to the front end of a self-propelled vehicle, the prior art devices require complex linkages incapable of sustained operation without frequent servicing in an underground mine. The overall size of the above ground machines substantially limit their operating capability when placed in an underground environment. The known underground devices are also unacceptable due to their limited versatility to carry out a plurality of material handling operations and are not efficiently convertible from one use to another in an underground passageway.